- there was a confusion in gf imfreq, in the new case
where freq can be <0 (non real gf, or for product gf).
- index: is the matsubara n, as in the struct matsubara_freq
index can be >0 or <0
- linear_index : is the shift from the 0. It is always >0.
Fixed function to compute it.
- Also changed the construction of mesh_point in the generic iterator.
Before, was constructed with a mesh point of index 0
Now, added a new constructor on mesh_point_t, just taking the mesh
which construct the *first* mesh_point.
Fixed linear, discrete, product accordingly.
Added to the documentation of the concepts of gf.
- little details : code cleaning, clang formatting, along
with documentation writing for c++ gf.
- separated the mesh in small class for better doc.
- work on documentation : reorganize specialisation, ...
- All access to grid is now using the [] operator.
() always returns const, and is an evaluation over the domain.
- Now :
* () is always a call to evaluator (or a lazy expression).
* mesh_pt accepted by [] , both const and non const,
and not by ().
- Ported the libs (fourier et al.) but this break API.
